Matt McGrath, Environment Correspondent for BBC News, posted a short piece entitled A ‘magic bullet’ to capture carbon dioxide?
Which was introduced as follows:
“CO2 is a powerful warming gas but there’s not a lot of it in the atmosphere – for every million particles of air, there are 410 of CO2.
The gas is helping to drive temperatures up around the world, but the comparatively low concentration means it is difficult to design efficient machines to remove it.
But a Canadian company, Carbon Engineering, believes it has found a solution.
Air is exposed to a chemical solution that concentrates the CO2. Further refinements mean the gas can be purified into a form that can be stored or utilised as a liquid fuel.”
The ‘magic bullet’ in the title is of course clickbait, because anyone who has spent any time looking at all the ways we need to reduce emissions or to draw down CO2 from the atmosphere will know that we need a wide range of solutions. There is no single ‘magic bullet’.
Not specifically commenting on this story, but in a related piece about so-called ‘Negative Emissions Technologies’ (NETs), Glen Peters highlights the scale of the challenge facing any type of NET, which aims to remove CO₂ from the atmosphere.
To remove the excess CO₂, sufficient at least to keep below 2oC …
“essentially we need to build an industry that’s 3 to 4 times the size of the current oil & gas industry just to clean up our waste” (2nd April 2019)
The issue is one of both scale and timing. We need big interventions and we need them fast (or fast enough).
It would take time and considerable resources to scale up NETs, which are currently mostly still in their development phase, and so the immediate focus needs to be on other strategies including energy in the home, reduced consumption, rolling out renewables, changing diets, etc., for which the solutions are ready and waiting and just needed a massive push from Governments, industry and civil society.
Glen Peters stresses that the first priority is emissions reductions, rather than capture, although capture will be needed in due course either using natural methods, or technological ones, or some combination.
There are big questions hanging over NETs such as BECCS (Bio-Energy with Carbon Capture and Storage), which would require between 1 and 5 ‘Indias’ of land area to make the contribution needed. The continuing fertility of soils to grow plants for BECCS and competition for land-use for agriculture, are just two of the concerns raised.
The technology highlighted in the BBC piece is DAC (Direct Air Capture) which could – powered by renewables – have great potential and avoids land-use competition, but is energy intensive. As with BECCS, DAC used in sequestration mode would still need to overcome hurdles, such as the geological ones related to safely burying CO₂ in perpetuity (my emphasis)
My concerns with Carbon Engineering’s proposed application of DAC – for fuel to be used in transport – are as follows.
Firstly, road, rail, and even shipping, are being electrified, making fuel redundant. There is the competing hydrogen economy that would use fuel, but a non-carbon based one. Either way, this will rapidly decarbonise these parts of transport. Since transport is overall 25% of global emissions currently, this is a highly significant ‘quick win’ for the planet (within 2 or at most 3 decades).
Commercial Aviation is 13% of transport’s carbon emissions, but is less easy to electrify – at the scale of airliners travelling long-distance – because of the current energy density and weight of batteries (this could change in the future, as Professor Clare Grey explained during an episode of The Life Scientific).
Aviation is therefore just above 3% of global emissions (13% of 25%) from all sectors (albeit a probably increasing percentage). A development-stage technology being focused on just 3% of global emissions can hardly be framed as a ‘magic bullet’ to the climate crisis.
Secondly, in terms of Government financing, would we focus it on decarbonising road, or decarbonising aviation? I suggest the former not the latter if it came down to a choice.
DAC may be great to invest some money in, as development phase technology, but the big bucks needed immediately, to make a huge dent in emissions, are in areas such as road sector.
It is not a binary choice of course, but the issue with financing is timing and scale again. The many solutions we forge ahead with now must meet the test that they are proven (not futurism/ delayism solutions like nuclear fusion), can be scaled fast, and will contribute significantly to carbon reductions while also helping to transition society in positive ways (as for example, the solutions in Project Drawdown offer, with numerous ‘co-benefits’)
Finally, it is worth stressing that the focus for Carbon Engineering (and hence the BBC report) is on the capture of carbon dioxide, to be converted into hydrocarbons as fuel, for burning. This effectively recycles atmospheric carbon. It neither adds to, nor takes away, carbon dioxide through this cycle.
This therefore makes zero change to CO₂ in the atmosphere. It might be whimsically called Carbon Capture and re-Emission technology (CCE)!
So I think it was wrong of the BBC piece to give the impression that the goal was ‘Carbon Capture and Storage’ (CCS), whose aim is to draw down CO₂.
It is confusing to conflate CCE and CCS!
Especially when neither are magic bullets.
(c) Richard W. Erskine, 2019